Fig. 4: The effect of rotational dissociation on pair dynamics.

a A single trajectory calculation illustrates how CO dissociation and rotation affects the pair distances from a reference atom Fe to the C and O atoms. Fe-C (blue line) and Fe-O (red line) distances cross (horizontal arrow) and separate (vertical arrow) in space and time as the dissociating CO rotates 90°, which in turn produces the density modulations simulated in b using the experimental conditions. c We compare the average simulated pair density, evaluated at the spatiotemporal intersections of pair distances across all trajectories (color scale refers to contour lines), to the measured ΔPD (red-blue), correlating the observed density modulations with rotational dissociation. d The dissociation velocity and rotation frequency are estimated from the measured ΔPD modulations and compared to the expectation values from the simulation averaging all trajectories. Confidence intervals for the simulated data (red) are the widths of the dissociation velocity and rotation frequency distributions derived from all trajectories, while those for the experimental data (black) are obtained by weighting slopes inferred from the kinetic-model-predicted dissociation onset and experimental density modulations (Supplementary Note 6).